diff --git a/esphome/components/api/proto.h b/esphome/components/api/proto.h
index 2bf26c5957..936e732af1 100644
--- a/esphome/components/api/proto.h
+++ b/esphome/components/api/proto.h
@@ -192,9 +192,6 @@ class Proto64Bit {
   const uint64_t value_;
 };
 
-// Forward declaration needed for method declaration
-class ProtoMessage;
-
 class ProtoWriteBuffer {
  public:
   ProtoWriteBuffer(std::vector<uint8_t> *buffer) : buffer_(buffer) {}